class Solution {
public:
    string countAndSay(int n) {
		string ret="1";
		for(int i=1;i<n;i++)
		{
			string tmp;
			int len=ret.size();
			for(int left=0,right=0;right<len;)
			{
				while(ret[left]==ret[right]&&right<len)right++;
				tmp+=to_string(right-left)+ret[left];
				left=right;
			}
			ret=tmp;
		}
		return ret; 
    }
};
